Unicorn helmet



FIG. 1 is a front left perspective view of a unicorn helmet showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The evenly broken lines in the figures represent portions of the unicorn helmet that form no part of the claimed design. The unevenly broken lines represent the boundary of the claim and form no part thereof. 

CLAIM I claim the ornamental design for a unicorn helmet, as shown and described. 